1. Field of the Invention
The present invention relates to a medical imaging apparatus, such as a fundus camera to be used for a group examination, at an ophthalmologist's office, and the like.
2. Description of the Related Art
In these days, fundus imaging using a fundus camera has been widely used for screening in group examinations, and diagnosis for ophthalmological disease. In recent years, a method for recording a fundus image as digital data has been widely used. Imaged data is recorded in portable type recording media and hard disk drives built in personal computers (PCs).
In order to improve efficiency of fundus imaging, fundus cameras capable of concurrently performing a plurality of fundus imaging operations have become widely used. Particularly, when fluorescence imaging using a fluorescence agent is performed in an ophthalmologist's office, in many cases, when several minutes or several tens of minutes have passed after a large number of fundus images are taken at an initial stage at which intravenous injection of a fluorescence agent is performed, later stage imaging is performed.
Accordingly, a waiting time occurs while fluorescence imaging is performed on a subject. Thus, an operator may perform color imaging during the waiting time. Thereby, examination efficiency can be improved.
In a fundus camera discussed in, e.g., Japanese Patent Application Laid-Open No. 2006-345955, color imaging of a subject can be performed while fluorescence imaging of the same subject is performed. However, when fluorescence imaging and color imaging of a subject are concurrently performed, an operator may not recognize in which imaging mode the current imaging is performed.
Thus, in the fundus camera discussed in Japanese Patent Application Laid-Open No. 2006-345955, when a predetermined number of images of a subject are captured in color after the color imaging is once performed while the fluorescence imaging is performed, the current imaging mode is automatically returned to the fluorescence imaging mode. As a result, an operator can take images of a subject without confusion.
As described above, in recent years, with rapid digitalization of fundus cameras, requests for concurrently performing a plurality of fundus imaging operations have increased. Particularly, because a film exchange operation needed when a subject is changed is not necessary because of the digitalization of fundus cameras, requests for performing fundus imaging of another subject during the waiting time for a subject have increased.
However, when the fundus imaging is excessively inserted in the fundus imaging of the subject, the fundus imaging that is originally to be performed cannot be performed at a proper timing.
For example, when fluorescence imaging of a fundus of a subject's eye is performed in an ophthalmologist's office or the like, fundus imaging is performed by intravenously injecting a fluorescence agent into the subject. The intravenously injected fluorescence agent circulates in the subject's body. Eventually, the fluorescence agent reaches a fundus part of the subject's eye. An operator must take an image of the fundus part of the subject's eye at a timing when the fluorescence agent reaches a diseased portion of the fundus part of the subject's eye.
However, when imaging is concurrently performed on a plurality of subjects, a time for changing the subjects is necessary. Accordingly, a proper timing for capturing each image may be missed during the changing of the subjects.
Even when the changing of the subjects is smoothly performed, the proper timing of the fluorescence imaging may be missed if focus adjustment and alignment adjustment in the fundus camera take a lot of time.
Thus, when a plurality of subjects are concurrently imaged, a risk of missing the proper timing of imaging may occur in exchange for high examination efficiency. When an operator misses the proper timing of imaging of a subject, the operator must ask the subject for re-imaging.
This not only reduces the examination efficiency from a viewpoint of improving the efficiency but also imposes a large burden on a subject. In order to avoid the risk described above, operators must give up concurrent imaging of a plurality of subjects. As a result, the improvement of the examination efficiency may not be achieved.